RCA 21LU8 Vacuum Tube Valve NOS NIB Matched Pair 6AU6

RCA 21LU8 Vacuum Tube Valve NOS NIB Matched Pair 6AU6This new old stock, new in box RCA 21LU8 tube tested to spec on our Paul Hart calibrated TV7 U. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS. 1. MOST OF THE TUBES WE SELL ARE OVER 70 YEARS OLD. WE CANNOT GUARANTEE FOR FAILURES AFTER POWER UP AS THERE IS NO WAY TO DETERMINE

It also sounded great in my Schiit Audio Vali 2 headphone amplifier

selected 6L6s

This Motorola 107

and dynamics even though these amplifiers use 6J5s

new in box Sylvania 10GK6 tubes tested to spec on our Paul Hart-calibrated TV7/U

These four RCA and Cunningham number / type 27 tubes tested as low goodand good on our Paul Hart-calibrated TV7/U

They measured 62 and 76 where minimum (65%) is 46 and 100% is 71

rectangular mica spacers (with rounded edges on top)

likely Tung-Sol-MANUFACTURED) measured 31 while Tube Two (no silkscreening 6AK5-LABELED

Two are RCA 956s and the third is a Tung-Sol JAN-CTL-956 / VT-238

The spine is in fine shape with no loose pages and APPEARS to be leather-bound

new in box RCA 6AD7G tube tested to spec on our Paul Hart-calibrated TV7/U